Pulmonary Delivery of Aerosolized Chloroquine and Hydroxychloroquine to Treat COVID-19: In Vitro Experimentation to Human Dosing Predictions.

In vitro screening for pharmacological activity of existing drugs showed chloroquine and hydroxychloroquine to be effective against severe acute respiratory syndrome coronavirus 2. Oral administration of these compounds to obtain desired pulmonary exposures resulted in dose-limiting systemic toxicity in humans. However, pulmonary drug delivery enables direct and rapid administration to obtain higher local tissue concentrations in target tissue. In this work, inhalable formulations for thermal aerosolization of chloroquine and hydroxychloroquine were developed, and their physicochemical properties were characterized. Thermal aerosolization of 40 mg/mL chloroquine and 100 mg/mL hydroxychloroquine formulations delivered respirable aerosol particle sizes with 0.15 and 0.33 mg per 55 mL puff, respectively. In vitro toxicity was evaluated by exposing primary human bronchial epithelial cells to aerosol generated from Vitrocell. An in vitro exposure to 7.24 µg of chloroquine or 7.99 µg hydroxychloroquine showed no significant changes in cilia beating, transepithelial electrical resistance, and cell viability. The pharmacokinetics of inhaled aerosols was predicted by developing a physiologically based pharmacokinetic model that included a detailed species-specific respiratory tract physiology and lysosomal trapping. Based on the model predictions, inhaling emitted doses comprising 1.5 mg of chloroquine or 3.3 mg hydroxychloroquine three times a day may yield therapeutically effective concentrations in the lung. Inhalation of higher doses further increased effective concentrations in the lung while maintaining lower systemic concentrations. Given the theoretically favorable risk/benefit ratio, the clinical significance for pulmonary delivery of aerosolized chloroquine and hydroxychloroquine to treat COVID-19 needs to be established in rigorous safety and efficacy studies. Graphical abstract.

Complementary autophagy inhibition and glucose metabolism with rattle-structured polydopamine@mesoporous silica nanoparticles for augmented low-temperature photothermal therapy and in vivo photoacoustic imaging.

Rattle-structured nanoparticles with movable cores, porous shells and hollow interiors have shown great effectiveness in drug delivery and cancer theranostics. Targeting autophagy and glucose have provided alternative strategies for cancer intervention therapy. Herein, rattle-structured polydopamine@mesoporous silica nanoparticles were prepared for in vivo photoacoustic (PA) imaging and augmented low-temperature photothermal therapy (PTT) via complementary autophagy inhibition and glucose metabolism. Methods: The multifunctional rattle-structured nanoparticles were designed with the nanocore of PDA and the nanoshell of hollow mesoporous silica (PDA@hm) via a four-step process. PDA@hm was then loaded with autophagy inhibitor chloroquine (CQ) and conjugated with glucose consumer glucose oxidase (GOx) (PDA@hm@CQ@GOx), forming a corona-like structure nanoparticle. Results: The CQ and GOx were loaded into the cavity and decorated onto the surface of PDA@hm, respectively. The GOx-mediated tumor starvation strategy would directly suppress the expression of HSP70 and HSP90, resulting in an enhanced low-temperature PTT induced by PDA nanocore. In addition, autophagy inhibition by the released CQ made up for the loss of low-temperature PTT and starvation efficiencies by PTT- and starvation-activated autophagy, realizing augmented therapy efficacy. Furthermore, the PDA nanocore in the PDA@hm@CQ@GOx could be also used for PA imaging. Conclusion: Such a "drugs" loaded rattle-structured nanoparticle could be used for augmented low-temperature PTT through complementarily regulating glucose metabolism and inhibiting autophagy and in vivo photoacoustic imaging.

Speed of action and stage specificity of Bencha-loga-wichian, a Thai traditional antipyretic formulation, against Plasmodium falciparum and the chloroquine-potentiating activity of its active compounds, tiliacorinine and yanangcorinine.

ETHNOPHARMACOLOGICAL RELEVANCE: Bencha-loga-wichian (BLW), a Thai traditional antipyretic formulation, has been reported to have promising antiplasmodial activity, and it was previously revealed that tiliacorinine and yanangcorinine, isolated from Tiliacora triandra, were the active compounds. However, the mechanisms of action of BLW have not been investigated. In addition, these active compounds are bisbenzylisoquinoline alkaloids, many compounds of which have been reported to potentiate the efficacy of chloroquine. AIMS OF THE STUDY: To investigate the antiplasmodial mechanisms of action of BLW and evaluate the effects of chloroquine combined with tiliacorinine or yanangcorinine. MATERIALS AND METHODS: Chloroquine-resistant Plasmodium falciparum (PfW2) strains at the ring, trophozoite, and schizont stages were exposed to the extracts or compounds for 2, 4, 6, 8, 10, 12, 24 or 48 h. The percentages of parasitemia were determined by flow cytometry, and their morphologies were examined by Giemsa-stained smear to evaluate the speed of action and stage specificity. For the drug combination assay, a modified fixed-ratio isobologram method was used. RESULTS: The antiplasmodial activity of BLW possessed a slow onset of action and was the most effective against ring-stage parasites. After 48 h of extracts or compounds exposure, most of the treated parasites, at all stages, turned to the pyknotic form and could not recover even after extracts or compounds removal. The results suggested that these extracts and compounds could kill the parasites or possess parasiticidal effects. In addition, the combination of chloroquine with tiliacorinine or yanangcorinine demonstrated a synergistic effect, indicating that these compounds could potentiate chloroquine efficacy against chloroquine-resistant parasites. CONCLUSION: The antiplasmodial mechanisms of action of BLW appeared to differ from that of chloroquine and other current antimalarial drugs. In addition, tiliacorinine and yanangcorinine, the active compounds of BLW, could potentiate the efficacy of chloroquine. Accordingly, BLW was shown to be a good candidate for development as a new antimalarial and useful for drug combination therapy.

Does zinc supplementation enhance the clinical efficacy of chloroquine/hydroxychloroquine to win today's battle against COVID-19?

Currently, drug repurposing is an alternative to novel drug development for the treatment of COVID-19 patients. The antimalarial drug chloroquine (CQ) and its metabolite hydroxychloroquine (HCQ) are currently being tested in several clinical studies as potential candidates to limit SARS-CoV-2-mediated morbidity and mortality. CQ and HCQ (CQ/HCQ) inhibit pH-dependent steps of SARS-CoV-2 replication by increasing pH in intracellular vesicles and interfere with virus particle delivery into host cells. Besides direct antiviral effects, CQ/HCQ specifically target extracellular zinc to intracellular lysosomes where it interferes with RNA-dependent RNA polymerase activity and coronavirus replication. As zinc deficiency frequently occurs in elderly patients and in those with cardiovascular disease, chronic pulmonary disease, or diabetes, we hypothesize that CQ/HCQ plus zinc supplementation may be more effective in reducing COVID-19 morbidity and mortality than CQ or HCQ in monotherapy. Therefore, CQ/HCQ in combination with zinc should be considered as additional study arm for COVID-19 clinical trials.

5-Fluorouracil in combination with deoxyribonucleosides and deoxyribose as possible therapeutic options for the Coronavirus, COVID-19 infection.

The recent global pandemic created by the Coronavirus SARS-CoV-2, started in Wuhan, China in December 2019, has generated panic, both in term of human death (4-5% of infected patients identified through testing) and the global economy. Human sufferings seem to be continuing, and it is not clear how long this will continue and how much more destruction it is going to cause until complete control is achieved. One of the most disturbing issues is Covid-19 treatment; although a large number of medications, previously used successfully with other viruses (including Chinese herbal medicines and anti-malaria drugs), are under consideration, there remain questions as to whether they can play a satisfactory role for this disease. Global attempts are ongoing to find the drugs for the treatment of this virus but none of the antiviral drugs used for treatment of other human viral infection is working and hence attempts to find new drugs are continuing. Here the author is proposing that 5-Fluorouracil (5-FU) which when used on its own is failing as an antiviral agent due to the removal of this compound by proof reading ability exceptionally found in Coronaviruses. The author here is proposing to test 5-FU in combination with a number of deoxynucleosides on animal models infected with this Covid-19. Should encouraging results ensue, therapies could then be tried on patients.

Gallbladder Cancer Progression Is Reversed by Nanomaterial-Induced Photothermal Therapy in Combination with Chemotherapy and Autophagy Inhibition.

INTRODUCTION: Gallbladder cancer (GBC) is the most common malignancy in biliary tract with extremely poor prognosis. Photothermal therapy (PTT) shows great promises for tumor therapy, which causes tumor cell death via selectively directed heating released by nanoparticles under the near-infrared irradiation. Through degrading damaged organelles and misfolded proteins in autophagosomes, autophagy plays a vital role in maintaining the intracellular homeostasis. The present study attempted to combine chemotherapy and autophagy blocking with PTT. MATERIALS AND METHODS: We purchased multi-walled carbon nanotubes from Nanostructured and Amorphous Materials and performed PTT using an 808-nm diode laser. The cytotoxic effects of PTT and chemotherapy in vitro were assessed by cell viability analysis. The effects of PTT and chemotherapy on autophagy in vitro were assessed by GFP-LC3 and Western blot. And these results were confirmed by in vivo experiment. RESULTS: Both PTT and chemotherapy could trigger cytoprotective autophagy to tolerate the cellular stresses and prolong the survival of GBC cell; therefore, the blocking of autophagy could enhance the efficacy of PTT and chemotherapy in GBC treatment in vitro and in vivo. CONCLUSION: Chemotherapeutic drug doxorubicin and autophagy inhibitor chloroquine could enhance the efficacy of nanoparticle-mediated hyperthermia in GBC.

Inhibition of autophagy enhances the targeted therapeutic effect of sorafenib in thyroid cancer.

The multi-target kinase inhibitor sorafenib has been approved for the treatment of patients with advanced differentiated thyroid cancer. However, different sensitivities to sorafenib have been observed, and few patients have benefited from sorafenib treatment in the long term. In the event of acquired resistance to sorafenib it is not beneficial to continue treatment in most patients. Autophagy can be induced in a variety of cancer treatments and plays an important role in cancer treatment. The role of autophagy in sorafenib treatment of thyroid cancer has not been fully demonstrated. The present study investigated whether autophagy is activated by sorafenib during the treatment of thyroid cancer, examined the underlying mechanisms, and explored potential strategies to enhance the therapeutic sensitivity of sorafenib. Chloroquine (CQ) is an autophagy inhibitor that has been reported to increase sensitivity to various cancer treatments. Thyroid cancer xenograft model mice were treated with sorafenib, CQ, or a combination of sorafenib and CQ. We observed that CQ or sorafenib treatment suppressed tumor growth, while mice treated with the combination of sorafenib and CQ displayed significantly reduced tumor growth compared with those treated with sorafenib or CQ alone. Western blotting results indicated that sorafenib concurrently inhibited the activities of the MAPK and AKT/mTOR pathways in thyroid cancer. Autophagy was activated by sorafenib in thyroid cancer, both in vitro and in vivo, which was at least in part due to suppression of the AKT/mTOR pathway. Combination treatment including CQ could inhibit the autophagic flux induced by sorafenib. Silencing the key autophagy gene ATG5 using small interfering RNA also increased the anticancer effect of sorafenib. In summary, the present study revealed that inhibition of autophagy enhances the anticancer effect of sorafenib, and the combination of CQ with sorafenib treatment represents a potential therapeutic strategy for treating advanced differentiated thyroid cancer.

Chloroquine, a FDA-approved Drug, Prevents Zika Virus Infection and its Associated Congenital Microcephaly in Mice.

Zika virus (ZIKV) has become a global public health emergency due to its rapidly expanding range and its ability to cause severe congenital defects such as microcephaly. However, there are no FDA-approved therapies or vaccines against ZIKV infection. Through our screening of viral entry inhibitors, we found that chloroquine (CQ), a commonly used antimalarial and a FDA-approved drug that has also been repurposed against other pathogens, could significantly inhibit ZIKV infection in vitro, by blocking virus internalization. We also demonstrated that CQ attenuates ZIKV-associated morbidity and mortality in mice. Finally, we proved that CQ protects fetal mice from microcephaly caused by ZIKV infection. Our methodology of focusing on previously identified antivirals in screens for effectiveness against ZIKV proved to be a rapid and efficient means of discovering new ZIKV therapeutics. Selecting drugs that were previously FDA-approved, such as CQ, also improves the likelihood that they may more quickly reach stages of clinical testing and use by the public.

Autophagy inhibition enabled efficient photothermal therapy at a mild temperature.

The heterogeneously-distributed hyperthermia in nanomaterial-mediated photothermal therapy commonly results in incomplete tumor eradication and serious damage of health tissue. Here, we found autophagy was activated in cancer cells underwent photothermal therapy and the inhibition of autophagy significantly enhanced the efficacy of photothermal killing of cancer cells. A formulation of chloroquine-loaded polydopamine nanoparticles was developed for sensitized photothermal cancer therapy, and the in vitro and in vivo study demonstrated that inhibition of autophagy remarkably augmented the efficacy of photothermal therapy, leading to efficient tumor suppression at a mild temperature. The regulation of autophagy provides a new route to increase the efficacy of photothermal cancer therapy.

Immunomodulatory proteins FIP-gts and chloroquine induce caspase-independent cell death via autophagy for resensitizing cisplatin-resistant urothelial cancer cells.

BACKGROUND: Chloroquine, a lysosomal inhibitor, is used for malaria, rheumatoid arthritis, and lupus erythematosus therapy. In our previous study, FIP-gts, an immunomodulatory protein from Ganoderma tsugae, inhibited cell viability in lung cancer cells and urothelial cancer cells. Urothelial carcinoma is the most common type of bladder cancer. Cisplatin resistance is an important issue in urothelial carcinoma therapy. PURPOSE: The aim of this study is to investigate the effect of combination treatment with FIP-gts and chloroquine on cytotoxicity to resensitize the cisplatin-resistant cells. METHODS: FIP-gts and chloroquine cytotoxicity were determined by evaluating CCK-8 assay. Cell death pathways, ROS and cell cycle arrested were analysed through flow cytometry and Western blot. ShRNA targeting to autophagy-related genes were tested to evaluate their autophagic cell death for resistant urothelial cells. RESULTS: Using CCK-8 assay, chloroquine increased FIP-gts-induced cytotoxicity in parental and cisplatin-resistant urothelial cancer cell lines. On flow cytometry, chloroquine enhanced FIP-gts-mediated sub-G1 accumulation, annexin V positive signal and mitochondrial membrane potential loss. Caspase-3/PARP cascade and z-VAD-fmk were performed to prove that FIP-gts and chloroquine induced caspase-independent cell death. Using H2DCFDA staining and flow cytometry, FIP-gts and chloroquine did not induce ROS production. N-acetyl cysteine, a ROS scavenger, inhibited the cytotoxicity and LC3-II accumulation in FIP-gts and chloroquine-treated N/P cells. To elucidate the role of autophagy in caspase-independent cell death by FIP-gts and chloroquine, LC3 shRNA were used to inhibit autophagy in N/P cells. The capabilities of FIP-gts and chloroquine to induce cytotoxicity and sub-G1 phase accumulation were abolished in autophagy-defective cells. This is the first study to reveal the novel function of FIP-gts in triggering caspase-independent cell death in cisplatin-resistant urothelial cancer cells. CONCLUSION: Chloroquine enhanced FIP-gts-induced autophagy dependent caspase-independent cell death via abundant autophagosome accumulation. Combination treatment with FIP-gts and chloroquine may provide a new strategy for urothelial cancer therapy.

Heterogeneous Pathology of Melasma and Its Clinical Implications.

Melasma is a commonly acquired hypermelanosis that affects sun-exposed areas of the skin, with frequent facial involvement. Its histologic manifestations are evident in the epidermis, extracellular matrix, and dermis. In addition to epidermal pigmentation, pathologic findings of melasma include extracellular matrix abnormality, especially solar elastosis. The disrupted basement membrane has been described in melasma with variable incidences. In the dermis, an increase in vascularity and an increase in the number of mast cells were observed, indicating that dermal factors have critical roles in the pathogenesis of melasma, despite the fact that melasma is characterized by epidermal hyperpigmentation. This review discusses such histologic characteristics of melasma, with consideration to their implications for melasma treatment.

In silico attempt for adduct agent(s) against malaria: Combination of chloroquine with alkaloids of Adhatoda vasica.

With the aim of controlling drug resistant Plasmodium falciparum, a computational attempt of designing novel adduct antimalarial drugs through the molecular docking method of combining chloroquine with five alkaloids, individually is presented. These alkaloids were obtained from the medicinal plant, Adhatoda vasica. From the obtained individual docking values of important derivatives of quinine and chloroquine, as well as, individual alkaloids and adduct agents of chloroquine with Adhatoda alkaloids as ligands, it was discernible that the 'adduct agent-1 with chloroquine and adhatodine' combination had the minimum energy of interaction, as the docking score value of -11.144 kcal/mol against the target protein, triosephosphate isomerase (TIM), the key enzyme of glycolytic pathway. Drug resistance of P. falciparum is due to a mutation in the polypeptide of TIM. Moratorium of mutant TIM would disrupt the metabolism during the control of the drug resistant P. falciparum. This in silico work helped to locate the 'adduct agent-1 with chloroquine and adhatodine', which could be taken up by pharmacology for further development of this compound as a new drug against drug resistant Plasmodium.

Arginine deprivation by arginine deiminase of Streptococcus pyogenes controls primary glioblastoma growth in vitro and in vivo.

Arginine auxotrophy constitutes a weak point of several tumors, among them glioblastoma multiforme (GBM). Hence, those tumors are supposed to be sensitive for arginine-depleting substances, such as arginine deiminase (ADI). Here we elucidated the sensitivity of patient-individual GBM cell lines toward Streptococcus pyogenes-derived ADI. To improve therapy, ADI was combined with currently established and pre-clinical cytostatic drugs. Additionally, effectiveness of local ADI therapy was determined in xenopatients. Half of the GBM cell lines tested responded well toward ADI monotherapy. In those cell lines, viability decreased significantly (up to 50%). Responding cell lines were subjected to combination therapy experiments to test if any additive or even synergistic effects may be achieved. Such promising results were obtained in 2/3 cases. In cell lines HROG02, HROG05 and HROG10, ADI and Palomid 529 combinations were most effective yielding more than 70% killing after 2 rounds of treatment. Comparable boosted antitumoral effects were observed after adding chloroquine to ADI (>60% killing). Apoptosis, as well as cell cycle dysregulation were found to play a minor role. In some, but clearly not all cases, (epi-) genetic silencing of arginine synthesis pathway genes (argininosuccinate synthetase 1 and argininosuccinate lyase) explained obtained results. In vivo, ADI as well as the combination of ADI and SAHA efficiently controlled HROG05 xenograft growth, whereas adding Palomid 529 to ADI did not further increase the strong antitumoral effect of ADI. The cumulative in vitro and in vivo results proved ADI as a very promising candidate therapeutic, especially for development of adjuvant GBM combination treatments.

Artesunate versus chloroquine infection-treatment-vaccination defines stage-specific immune responses associated with prolonged sterile protection against both pre-erythrocytic and erythrocytic Plasmodium yoelii infection.

Sterile protection against malaria infection can be achieved through vaccination of mice and humans with whole Plasmodium spp. parasites. One such method, known as infection-treatment-vaccination (ITV), involves immunization with wild type sporozoites (spz) under drug coverage. In this work, we used the different effects of antimalarial drugs chloroquine (CQ) and artesunate (AS) on blood stage (BS) parasites to dissect the stage-specific immune responses in mice immunized with Plasmodium yoelii spz under either drug, as well as their ability to protect mice against challenge with spz or infected RBCs (iRBCs). Whereas CQ-ITV induced sterile protection against challenge with both spz and iRBCs, AS-ITV only induced sterile protection against spz challenge. Importantly, AS-ITV delayed the onset of BS infection, indicating that both regimens induced cross-stage immunity. Moreover, both CQ- and AS-ITV induced CD8(+) T cells in the liver that eliminated malaria-infected hepatocytes in vitro, as well as Abs that recognized pre-erythrocytic parasites. Sera from both groups of mice inhibited spz invasion of hepatocytes in vitro, but only CQ-ITV induced high levels of anti-BS Abs. Finally, passive transfer of sera from CQ-ITV-treated mice delayed the onset of erythrocytic infection in the majority of mice challenged with P. yoelii iRBCs. Besides constituting the first characterization, to our knowledge, of AS-ITV as a vaccination strategy, our data show that ITV strategies that lead to subtle differences in the persistence of parasites in the blood enable the characterization of the resulting immune responses, which will contribute to future research in vaccine design and malaria interventions.

An in vivo drug screening model using glucose-6-phosphate dehydrogenase deficient mice to predict the hemolytic toxicity of 8-aminoquinolines.

Anti-malarial 8-aminoquinolines drugs cause acute hemolytic anemia in individuals with glucose-6-phosphate dehydrogenase deficiency (G6PDD). Efforts to develop non-hemolytic 8-aminoquinolines have been severely limited caused by the lack of a predictive in vivo animal model of hemolytic potential that would allow screening of candidate compounds. This report describes a G6PDD mouse model with a phenotype closely resembling the G6PDD phenotype found in the African A-type G6PDD human. These G6PDD mice, given different doses of primaquine, which used as a reference hemolytic drug, display a full array of hemolytic anemia parameters, consistently and reproducibly. The hemolytic and therapeutic indexes were generated for evaluation of hemotoxicity of drugs. This model demonstrated a complete hemolytic toxicity response to another known hemolytic antimalarial drug, pamaquine, but no response to non-hemolytic drugs, chloroquine and mefloquine. These results suggest that this model is suitable for evaluation of selected 8-AQ type candidate antimalarial drugs for their hemolytic potential.

Murine toxicology and pharmacokinetics evaluation of retinoic acid metabolism blocking agent (RAMBA), VN/12-1.

PURPOSE: Novel retinoic acid metabolism blocking agent (RAMBA), VN/12-1, is a highly potent anti-cancer agent that induces autophagy. Its combination with autophagy inhibitor chloroquine (CHL) has been shown to synergistically enhance apoptosis in breast cancer cells. The purpose of this study was to determine the toxicity and pharmacokinetic profile of VN/12-1 and its combination with CHL. METHODS: Preliminary toxicology of VN/12-1 was determined using female SCID mice (n = 4 for each group). ATRA was used for comparison. We selected four different doses of VN/12-1 and ATRA. Two of the doses were low and less frequent (2.5 and 5 mg/kg twice a week), and the remaining doses were high and more frequent (10 and 20 mg/kg every day). The dose of CHL was 50 mg/kg twice a week. For pharmacokinetic (PK) study, 20 mg/kg of VN/12-1 was injected subcutaneously (s.c.) into the mice, and their plasma was collected at various intervals (n = 2) and analyzed by HPLC. RESULTS: The lower and less frequent doses of VN/12-1 and ATRA were found to be least toxic. However, high and more frequent doses of these compounds were toxic to the mice. PK results showed that VN/12-1 has a half-life of 6 h. The area under the curve (AUC) for VN/12-1 was 83.78 h µg/ml. CONCLUSIONS: VN/12-1 and ATRA are non-toxic when used as 5 mg/kg twice a week as single agents or in combination with CHL. The favorable PK properties of VN/12-1 can potentially be used for its further advanced pre-clinical and clinical development.

Therapeutic effects of various solvent fractions of Alstonia boonei (apocynaceae) stem bark on Plasmodium berghei-induced malaria.

Malaria, the most important parasitic disease afflicting man is the leading cause of mortality and morbidity in the world. Chemotherapy remains the mainstay for the treatment and prevention of the disease in the absence of an effective vaccine. The incidence of resistance of malaria parasites to chemotherapy is increasing and complicated. This study was therefore undertaken in order to evaluate the therapeutic effects of fractions of the stem bark of A. boonei on P. berghei-induced malaria using chloroquine as control. Different doses (200 mg/kg and 400 mg/kg body weight) of methanolic extract (ME), n-hexane (HF), chloroform (CF), ethylacetate(EF) and aqueous (AF) fractions of the stem bark of A. boonei were administered orally to albino mice. Five milligrammes chloroquine base per kilogramme body weight (5 mg/kg bw) was used as positive control while the negative control mice received only the vehicle (5% v/v tween 80). The results obtained showed that the 400 mg/kg bw dose was more effective with respect to the parasite clearance than the 200 mg/kg bw dose. The 400 mg/kg bw dose of ME gave 68.1% percent parasite clearance. The CF gave the highest clearance of 98.4% at 400 mg/kg bw after 7 days treatment while chloroquine at 5 mg/kg bw gave 100% parasite clearance. The order of increasing potency of the fractions (parasite clearance) was (EF 50.0% < AF 60.3% < HF 63.1%, < CF 98.4%) indicating that the active principle in the stem bark was highest in the CF. Percentage parasitemia following exposure to these fractions also decreased in all groups in the same order and was only significant (p < 0.05) in CF (0.11%) compared to the untreated control group. The ME of A. boonei also caused increase in PCV by 15.5%. Purification enhanced PCV value as the HF and CF fractions gave 19.0% and 24.5% increases, respectively. However, 31.5% increase in PCV was obtained in the albino mice treated with chloroquine. The EF and AF gave increase of 10.0% and 11.0% increase relative to the negative control treated mice. The high bioactivity of CF and HF indicate that the putative compound(s) in A. boonei are lipophillic and further purification could enhance greater activity. Further work is required to isolate the bioactive compound for a promising antimalarial drug from the chloroform fraction.

A comparison of iron and folate with folate alone in hematologic recovery of children treated for acute malaria.

Concern has been raised that iron supplementation for treatment of acute malaria may worsen the severity of malaria. We compared the effect of iron and folate with folate alone on hematologic recovery in children treated for acute malaria. We randomized 82 children 6-60 months of age from Nigeria with smear-positive malaria and anemia (hematocrit < 33%) to receive iron (2 mg/kg/day) plus folate (5 mg/day) or folate alone in addition to antimalarial drugs. The mean ± SD hematocrit at baseline was 28.5% ± 2.9%. At four weeks, the mean hematocrit increased by 2.5% ± 1.6% in the iron plus folate group and by 1.4% ± 1.0% in the folate alone group (P = 0.001). Baseline hematocrit, iron supplementation, weight for height, and weekly meat intake were significant predictors of final hematocrit. The effect of iron was not significantly modified by baseline hematocrit, weekly meat intake, nutritional status, mother's education, sex, or age of the child. Iron supplementation improved hematologic recovery in children with malarial anemia.

Chemotherapeutic interaction between Khaya grandifoliola (WELW) CDC stem bark extract and two anti-malarial drugs in mice.

In malarial endemic countries especially in the tropics, conventional antimalarial drugs are used with herbal remedies either concurrently or successively. Khaya grandifoliola is one of such popular herbs used in the treatment of malaria.Various doses of ethanol extract of K. grandifoliola stem bark (50-400 mg/kg/day) were administered orally to Swiss albino mice infected with Plasmodium yoelii nigerense. A dose of 100 mg/kg/day of the extract was also combined with 2.5 mg/kg/day of chloroquine or 6.25 mg/kg/day of halofantrine in both early and established malaria infection test models. The results showed that in the early malaria infection test, K. grandifoliola in combination with chloroquine or halofantrine elicited enhanced antiplasmodial effect in the established infection, there was significantly greater parasite clearance following administration of the combination when compared to the effects of K. grandifoliola or the conventional drugs alone. The mean survival period of parasitized animals was also enhanced by the extract/halofantrine combination. Lower therapeutic doses of halofantrine may be required to potentiate parasite clearance when used in combination with K. grandifoliola. This may constitute great advantage to halofantrine which is associated with cardiotoxicity at high doses.